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    <script>
        var arr1 = [1, 5, 6, 3, 5, 6, 7, 2, 3, 4];
        var arr2 = ['a', '2', 'b', 'a'];

        function unique(arr) {
            var newarr = [];
            for (i = 0; i < arr.length; i++) {
                if (newarr.indexOf(arr[i]) == -1) {
                    newarr.push(arr[i])
                }
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            return newarr;
        }

        console.log(unique(arr1));
        console.log(unique(arr2));
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